Annunciator and control system with specific application to internal combustion engines



D. W. SCHLICHER ANNUNCIATOR AND CONTROL SYSTEM WITH SPECIFIC May 19, 1970 APPLICATION T0 INTERNAL COMBUSTION ENG *iginal Filed July 24. 1967 INES 2 Sheets-Sheet 1 OUT PUT LOGIC IN PUT 5 INVENTOR.

HG I DAVID w. SCHLICHER ATTORNEY May 19, 1970 D. W. SCHLICHER ANNUNCIATOR AND CONTROL SYSTEM WITH SPECIFIC APPLICATION TO INTERNAL COMBUSTION ENGINES Original Filed July 24. 1967 FIG-3 2 Sheets-Sheet 2 FIG. 4

TRUTH TABLE INPUTS OUTPUTS RPoc'fi P 00 ofl FIG. 6

TRUTH TA INPUTS OUTPUT INVENTOR DAVID W. SCHLICHER BY C. M

ATTORNEY United States Patent Int. Cl. Glilm 15/00 US. Cl. 73--116 2 Claims ABSTRACT OF THE DISCLOSURE An annunciator and control system including annunciators adapted to indicate faults in internal combustion engine operation and a control means for shutting down the system or correcting the fault together with lockout means for rendering the first to act annunciator operative and to lock out all the other annunciators prior to resetting of the system.

CROSS REFERENCES A division of application for patent of David W. Schlicher for Annunciator and Control System With Specific Application to Internal Combustion Engines, Ser. No. 655,591, filed July 24, 1967.

FIELD OF THE INVENTION Annunciators adapted to indicate faults in the operation of internal combustion engines together with a control for shutting down the engine or correcting the fault.

PRIOR ART Annunciators in which the circuits therefor are independent of one another.

SUMMARY OF THE INVENTION The invention resides in providing intercommunicating circuits between the annunciators and by means of which the operation of one annunciator locks out all the other annunciators thereby indicating only the first fault to occur.

To simplify the drawings and description of the invention symbolic logic has been used and Boolean expressions for the various outputs are employed along with truth tables. In the instant case negative logic is employed and NOR gates and inverters have been used. A logical 1 thus represents a low voltage state while a logical 0 represents a high voltage state. It will, however, become evident that other gates may be used.

In the drawings:

FIG. 1 is a schematic diagram using Boolean gates and inverters and disclosing the invention in use for controlling the operation of a diesel engine.

FIG. 2 is a table showing the initial logic states of the various logic devices of the circuits disclosed in FIG. 1.

' FIG. 3 is a schematic diagram of the engine starting annuuciator section of the invention.

FIG. 4 is a truth table for the inputs and outputs of the circuits shown in FIG. 3.

FIG. 5 is a schematic diagram of the engine crank termination and lockout section.

FIG. 6 discloses the truth table for the crank termination circuit shown in FIG. 5.

FIG. 7 is a wiring diagram of the components of one of the NOR gates used in the invention.

As an example of the use of the invention it is assumed that the invention is to be used with a diesel engine. For controlling the operation of the engine one method is to ice control the flow of fuel to the same and an electrically operated valve not illustrated may be used for the purpose. Such an engine requires a starting motor for turning over the engine and in the event that the engine does not start, the usual practice is to shut off the starting motor, Wait for a short time and make another try. If after several tries the engine will not start it is customary to cease trying and ascertain and correct the fault. In addition, numerous other engine faults may occur such as oil failure, excessive temperature at various localities such as bearings, windings, etc., low voltage, low speed, low fuel, etc. One fault such as improper lubrication may cause several other faults such as reduced speed, low voltage, and temperature increase, thus making it impossible to readily ascertain the cause of the faults. The instant invention overcomes this disadvantage by maintaining the indication of the first fault to occur and locking out the indications of all the other faults. To simplify the disclosure only the indicating means for failure of the engine to start and oil failure have been disclosed though it will be readily comprehended that as many faults as desired may be indicated by the use of additional fault circuits.

The structure disclosed comprises a lubrication fault sensitive section A which operates a lubrication fault indicating section B. Similarly an engine overcrank detection section C operates an overcrank fault indicating section D. Both the sections B and D operate a control section G which stops the engine whenever B or D indicate a fault. A multivibrator section E provides alternate crankrest timing periods and energizes the starting motor through the crank control section F. Section H controls crank termination and lockout after the engine starts.

The section A comprises a normally closed oil pressure switch S1 which is connected to ground by means of a conductor 72. This switch is further connected by means of a conductor 73 to an inverter 74, which, in turn, is connected by a conductor 75 to input 2 of a two input NOR gate 76. Input 1 of this gate is connected to a time delay device 70 by means of conductor 71 which in turn is connected to inverter 68 by conductor 69. A conductor 16 connects inverter 68 to a centrifugally operated switch S2 which is grounded by conductor 18.

The section B includes three two input NOR gates 219, 221, and 223. The output of gate 76 is connected by a conductor 287 to input 1 of gate 219. The output of gate 219 is connected by means of a conductor 220 to the input 2 of gate 223. Input 1 of this gate is connected by a conductor 222 to the output of gate 221 while the output of gate 223 is connected by means of a conductor 226 to inverter 229. The output of gate 223 is further connected by means of conductors 224 and 225 to the inputs 2 of gates 219 and 221. This inverter is connected by means of a conductor 232 to the base of a transistor 233. A conductor 234 connects the emitter of said transistor ':to ground. The collector of said transistor is connected [by means of a conductor 235 to a lamp 236 which, in turn, is connected by means of a conductor 237 to a source of direct current V. The lamp 236 constitutes the lubrication fault annunciator.

The overcrank detection section C consists of two inverters 82 and 86 and a binary counter 84. This counter may be of ordinary construction and has not been shown in detail. Inverter 82 is connected by means of conductor 83 to the binary counter 84. This counter is connected by a conductor 85 to inverter 86.

The overcrank indicator D indcludes 3 NOR gates 119, 121, and 123. The input 1 of NOR gate 121 is connected to the conductor 231, which, in turn, is connected to input 1 of NOR gate 221. Input 2 of NOR gate 121 is connected by means of a conductor 125 to the output of NOR gate 123. The input 2 of NOR gate 119 is connected by means of a conductor 124 to the output of NOR gate 123. Input 1 of NOR gate 119 is connected by means of conductor 187 to inverter 86 previously referred to. The output of NOR gate 119 is connected by means of a conductor 120 to the input 1 of NOR gate 123. The output of NOR gate 121 is connected by means of a conductor 122 to the input 2 of NOR gate 123. The output of NOR gate 123 is connected by means of a conductor 126 to an inverter 129. This inverter is connected by means of a conductor 132 to the base of a transistor 133. The emitter of this transistor is connected by a conductor 134 to ground. The collector of transistor 133 is connected by means of a conductor 135 to a lamp 136 which serves as the annunciator for the section D of the invention. This lamp is further connected by conductor 137 to a source of voltage v.

The crank-rest timing section E utilizes a multivibrator which may be of ordinary construction. This multivibrator utilizes a NOR gate 58 having 3 inputs. Input 1 of this gate is connected by means of a conductor 46 to a resistor 47 which, in turn, is connected by a conductor 48 to ground. Input 2 of the gate 58 is connected by means of a conductor 7 to the conductor 16 previously referred to. Input 3 of this gate is connected by means of a conductor 65 to an inverter 66 which is connected by a conductor 67 to the conductor 231. The output of NOR gate 58 is connected by means of a conductor 59 to a capacitor 60 which, in turn, is connected by means of a conductor 61 to a resistor 63. This resistor is connected by a conductor 64 to a source of voltage VA. The conductor 61 is connected by means of another conductor 62 to the base of a transistor 54. The emitter of this transistor is connected by means of a conductor 51 to a resistor 50 which, in turn, is connected by means of a conductor 49 to ground. The emitter is further connected to inverter 53 by means of conductor 52. The collector of transistor 54 is connected by means of conductor 55 to resistor 56. This resistor is connected by a conductor 57 to said source of voltage VA. Said inverter 53 is further connected by means of conductor 40 to resistor 42 which is connected by a conductor 43 to capacitor 44. This capacitor is further connected to said input 1 of NOR gate 58.

The crank control section F utilizes a two input NOR gate 87. Input 2 of this gate is connected by a conductor 41 to conductor 40 previously referred to. The output of NOR gate 87 is connected by a conductor 77 to an inverter 78. This inverter is connected by means of a conductor 79 to a solenoid and other mechanism 80 for cranking the engine.

The control section G of the invention utilizes a triple input NOR gate 27. Input 1 of this gate is connected by means of a conductor 128 to conductor 126. Input 3 of this gate is connected by means of a conductor 228 to the conductor 226. The output of gate 27 is connected by means of a conductor 30 to an inverter 38. Inverter 38 is connected by a conductor 39 to a solenoid and mechanism 88 for controlling the flow of fuel to the engine. A conductor 31 is connected to conductor 30 and also to conductor 231.

For starting up the system a switch 153 is employed which is connected by means of a conductor 92 to ground. The switch S3 is further connected by a conductor 91 to an inverter 89 which is connected by means of a conductor 90 to the input 2 of NOR gate 27.

The crank termination section H includes two inverters, 8 and 9. The output of the inverter 9 is connected by means of a conductor 13 to the input 2 of a NOR gate 10. The output of inverter 8 is similarly connected by means of a conductor 19 to input 1 of said NOR gate 10. The output of NOR gate is connected by means of a conductor 14 to the input 2 of a NOR gate 11. The output of this NOR gate is connected by means of a conductor 21 to an inverter 12. A conductor connects the output of inverter 12 to the input of inverter 9. The in- 4 put 1 of NOR gate 11 is connected by means of a conductor 17 to conductor 16 previously referred to.

The operation of the invention is as follows: The table shown in FIG. 2 gives the initial state of all of the logic elements shown in FIG. 1. To crank the engine switch S3 is closed which applies a logical 1 to inverters 8 and 89. Referring to the diagram in FIG. 5 and the truth table in FIG. 6 it is seen that with the input at switch S3 changing from 0 to 1 and with the input at switch S2 equal to 0 the output of inverter 12 remains in its previous state which was a logical 0. The logical O. The logical 1 input to NOR 89 causes the following changes of state to occur: NOR 89 output becomes a logical 0 which in effect makes the P input of FIG. 3 equal to a logical O and unlocks all the fault indicator circuits. Specifically in FIG. 1, input 2 of NOR 27 is a logical 0 which changes the output to logical 1. This output is applied to inverter 38 which changes state and causes the solenoid and accessories 88 to be energized and changes inputs 1 of NOR 121 and 221 to a logical 0. This now places control of NOR 123 and 223 upon a change of state or NOR 119 and 219 respectively and this will occurs anytime a fault indication is obtained. The logical 1 output of NOR 27 is also applied to inverter 66 which applies a logical 0 to input 3 of NOR 58 and starts the asta'ble multivibrator E. The output of the multivibrator is applied to the input 2 of NOR 87 where a logical 0 represents a period of cranking and logical 1 represents a period of resting. Cranking is accomplished by applying the changing output of NOR 87 to inverter 78 which controls the crank energization. The crank period which is the order of 10 to 20 seconds is controlled by resistor 63 and capacitor 60. The rest period is determined by values of resistor 42 and capacitor 44. These alternate crank-rest periods continue until the engine starts or until the binary counter 84 counts the preset number of cranks at which time a logical 0 is applied to inverter 86 which, in turn, applies a logical 1 to input 1 of NOR 119. This represents the R input to NOR 119 of FIGS. 1 and 3 and the truth table of FIG. 4 shows that the indication output Q now goes to a logical 1 and the control output Q+ P goes to a logical O.

The indication output from NOR 123 is applied to inverter 129 which causes the overcrank lamp 136 to light and to input 2 of NOR 119 and NOR 121 which latches on this fault circuit. The control output from NOR 27 deenergizes the engine through inverter 38 and locks out the low-oil-presure fault circuit A through NOR 221. This can be seen more clearly by referring to the truth table in FIG. 4. It will become evident with respect to the over crank circuit that the input P is 0, so after R once becomes 1, the input remains latched in the 1 state. With reference to the low-oil-pressure fault circuit, the P input is the Q output of the over crank circuit and since this is 1 the Q output remains in the same state regardless of the R input.

The operation just described was based on the assumption that three was no engine start. In the event of a start, speed switch S2 closes when the engine reaches the desired speed. A logical 1 is then applied to input 1 of NOR 11, input 2 of NOR 58 and inverter 68. This terminates cranking, stops the multivibrator and starts the time delay device 70 operating. The oil pressure switch S1 must now open before time device 70 times out or NOR 76 would change state and indicate a low oil pressure fault. Op eration would then be the same as with the overcrank fault except that the function of the two fault circuits would be reversed. With switch S1 opening before the time delay device times out NOR 76 would not change state and the engine would continue running until shut down was desired and switch S3 was opened or until some monitored fault shut it down.

Although only two fault circuits are shown, any number of similar fault circuits could be added with the outputs feeding the corresponding number of inputs of NOR 27.

The advantages of the invention are manifest. The first fault to occur would indicate the origin of the same, and said fault corrected. Frequently one fault causes one or more other faults and an indication of the first fault and correction thereof might remove one or more of the other faults.

Changes in the specific form of the invention, as herein described, may be made within the scope of what is claimed without departing from the spirit of the invention.

Having described the invention, that is claimed as new and desired to be protected by Letters Patent is:

1. An annunciator and control system adapted to be used in an engine control system comprising:

(a) a first fault detecting means detecting failure of the engine to start,

(b) a first annunciating means operated by said first fault detecting means,

(c) a second fault detecting means,

((1) a second annunciating means operated by said second fault detecting means,

(e) control means operable by either of said fault detecting means,

(f) lock-out means actuated by said first or second fault detecting means and upon occurrence of the first fault, rendering the fault detecting means therefor operative to actuate the corresponding annunciating means and the control means operable and up on subsequent occurrence of a different fault rendering the corresponding annunciating means inoperative,

(g) said first fault detecting means including,

(h) engine cranking means,

(i) timing means producing alternating starting and rest periods periodically actuating said engine cranking means,

(j) over cranking monitoring means actuated upon cranking of the engine a predetermined number of times, and

(k) cranking terminating means actuated by said over cranking monitoring means and operating said first annunciating means.

2. An annunciator and control system according to claim 1 in which the timing means is an astable multivibrator producing a square Wave and periodically operating said engine cranking means.

References Cited UNITED STATES PATENTS 3,396,376 8/1968 Emerson 3404l5 X JERRY W. MYRACLE, Primary Examiner US. Cl. X.R. 340-415 

